const arr = [1,
    21,
    41,
    61,
    2,
    22,
    42,
    62,
    3,
    23,
    43,
    63,
    4,
    24,
    44,
    64,
    5,
    25,
    45,
    65,
    6,
    26,
    46,
    66,
    7,
    27,
    47,
    67,
    8,
    28,
    48,
    68,
    9,
    29,
    49,
    69,
    10,
    30,
    50,
    70,
    11,
    31,
    51,
    71,
    12,
    32,
    52,
    72,
    13,
    33,
    53,
    73,
    14,
    34,
    54,
    74,
    15,
    35,
    55,
    75,
    16,
    36,
    56,
    76,
    17,
    37,
    57,
    77,
    18,
    38,
    58,
    78,
    19,
    39,
    59,
    79,
    20,
    40,
    60,
    80,]

    

    console.log(arr.sort((pre, cur) => {
        return pre - cur
    }));